Mapping Mountains – Significant Name Changes – 100m Twmpau and Y Trechol – The Dominant Hills of Wales

Bryn y Gaer (SJ 313 574) 

There has been a Significant Name Change to a hill that is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales, with the summit height, bwlch height and their locations, the drop, dominance and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

The summit of Bryn y Gaer (SJ 313 574)

The criteria for the two listings that this name change applies to are:

100m Twmpau - Welsh hills at or above 100m and below 200m in height with 30m minimum drop, with an accompanying sub list entitled the 100m Sub-Twmpau with the criteria for this sub category being all Welsh hills at or above 100m and below 200m in height with 20m or more and below 30m of drop, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. 

The 100m Twmpau by Myrddyn Phillips

Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3^rd December 2015, and which is now available in its entirety on Mapping Mountains in Google Doc format. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The hill is adjoined to the Bryniau Clwyd group of hills which are situated in the north-eastern part of North Wales (Region A, Sub-Region A2), and it is positioned with the A550 road to its west, a minor road to its south and the B5373 road to its north-east, and has the village of Yr Hôb (Hope) towards the north-west. 

When the original 100m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was listed under the name of Caer Estyn, which is a prominent name that appears close to the summit of this hill on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is the name given the remains of an ancient hill fort that is positioned on this hill. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since publication of these P30 lists on Geoff Crowder’s v-g.me website there have been a number of Ordnance Survey maps made available online, some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website, whilst others are current and digitally updated such as the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map, and the interactive mapping on the Magic Maps and WalkLakes websites, and it is the Ordnance Survey series of Six-Inch maps that name this hill Bryn y Gaer. 

Extract from the Ordnance Survey series of Six-Inch maps

After parking my car and getting my boots on and just before setting out for this hill I commented to a woman, who appeared close to my car and who was taking her daughter out, what a beautiful morning it was, I asked if she was local and then asked about the name of the hill, she replied it’s known as Bryn y Gaer.  After visiting the hill and arriving back at my car I met a man walking his dog, he was also local and we chatted about the hill and I asked him about its name, he also replied that it is known as Bryn y Gaer. 

Therefore, the name this hill is now listed by in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales is Bryn y Gaer, and this was derived from the Ordnance Survey series of Six-Inch maps and substantiated by local enquiry.  As Bryn y Gaer is the name of the hill, this is prioritised in favour of the name of an ancient hill fort. 

 

The full details for the hill are: 

Group:  Bryniau Clwyd 

Name:  Bryn y Gaer

Previously Listed Name:  Caer Estyn 

OS 1:50,000 map:  117

Summit Height:  153.9m (LIDAR) 

Summit Grid Reference:  SJ 31381 57459 (LIDAR) 

Bwlch Height:  95.8m (LIDAR) 

Bwlch Grid Reference:  SJ 31774 58223 (LIDAR) 

Drop:  58.1m (LIDAR) 

Dominance:  37.74% (LIDAR) 

 

Myrddyn Phillips (December 2021)